SHAFAQNA – Unknown assailants have launched an arson attack on a mosque in central Sweden, injuring at least five people.

“Somebody threw an object through a closed window and afterwards a fire started inside,” police spokesman, Lars Franzell, said on Thursday.

The mosque is situated on the ground level of a building in the city of Eskilstuna, some 90 kilometers (55 miles) west of the capital, Stockholm.

“There were between 15 and 20 people in the premises,” Franzell added.

The five individuals who were injured were transferred to hospital to be treated for smoke inhalation, lacerations or other injuries.

Police said an investigation is underway; however, no suspects have been identified yet.

The arson attack comes amid growing far-right anti-Muslim extremism and a political dispute over immigration in Sweden, which has traditionally been seen as a refugee-friendly country.

In December, Swedish Prime Minister Stefan Loefven called the country’s first snap elections after the far-right Sweden Democrats torpedoed his government’s budget plan in a parliamentary vote.

The move to rebel against the government budget proposal was considered a major political breakthrough for Sweden Democrats, which became the country’s third-largest group in parliament in the September general elections. The far-right party holds strong views against immigration.